Aircraft include a weather antenna, such as an X-band slotted waveguide antenna, that is used during take off and landing to predict the presence of windshear in front of the aircraft. The X-band slotted waveguide antenna emits radiation into a relatively large azimuthal angle.
Millimeter wave (MMW) synthetic or enhanced vision systems for civil aviation are effective systems to provide visibility of objects located in fog, smoke, dust and other obscurants. Such synthetic vision systems would be useful if implemented to assist aircraft as it lands in areas that are foggy, smoky, dusty, or otherwise obscured. The millimeter wave antenna is generated by a microstrip antenna and emits radiation into a narrow beam azimuth angle that is appropriate for viewing the landing strip from a distance during take off and landing of an aircraft.
There is not enough available space within the radome of a civil transport or regional aircraft to scan a MMW antenna and to scan an X-band weather antenna. Thus, aircraft cannot simultaneously view the landing strip through obscurants and detect windshear in front of the plane.
Additionally, the cost of adding an additional antenna system to an aircraft makes an implementation of both an X-band slotted waveguide antenna and a dedicated MMW scanning antenna unlikely. The additional weight from a second antenna system reduces fuel efficiency of the aircraft and the range of the aircraft.
Even if room were available in the radome for both a MMW antenna and an X-band antenna, the signals emitted from the two antennae are likely to interfere with each other due to the two antenna structures interfering with the radiation pattern of the other antenna as they scan asynchronously.